Is this a common harpsichord technique in Bach's WTC 1 C-major Prelude?

Question

In Wanda Landowska's recording of the opening prelude to J.S. Bach's Well-Tempered Clavier, at the moment of dominant prolongation (shortly after the cued recording begins) she doubles the bass one octave lower.

But shortly afterwards, at the end of every measure she plays this lower octave one sixteenth note before playing the correct octave on the downbeat.

Is this just her own interpretation, or is there a technical reason for her to play this lower octave one sixteenth note before the actual octave? Does it make the rest of the keyboard more resonant, or something to that effect?

Answer 1

I do not know if this would be in the sense of Bach, but Bach did compose his harpsichord works for some standard range, while big harpsichords such as the ones Bach probably played did offer extended range. It is thus not unlikely that a gifted player at the time would have made use of this extra range.

About the early note: On a harpsichord you do not have a way of differentiating notes apart from when and how long you play them. This means that on harpsichord you occasionally need to do things differently do keep transparency (which on the piano can be done simply by emphasizing important notes). Now if we play an octave on a harpsichord there is no way to emphasize the top note, so it will generally sound like a single note and swallow the top note. So I guess to prevent this from happening she does not play both Gs in unison, but the proper one at the proper place and the additional one just a bit early.

Answer 2

This would be her personal way of increasing the intensity of the piece with the added octave. Bach did not indicate this. As for the sixteenth note out, that is a style that some keyboard players adopt, probably to give clarity of line. Personally, I find it disruptive and unnecessary. However, you can hear this style of playing a lot from prominent pianists and keyboard players.

Answer 3

I'm not sure how common different styles of harpsichord were at different points in history, but many harpsichords have two manuals, multiple courses of strings playing at different octaves, ways of controlling which courses of strings are played by the manuals, and also in many cases a "dog ear coupler" which will cause notes played on the lower manual to also be played on the upper. Thus, the fact that a pitch is played simultaneously on two strings an octave apart may or may not indicate that the performer is pressing two keys.

On the harpsichords I've played, when multiple strings are played by a key, it would be possible to play the notes at distinct times by playing the string absurdly slowly and deliberately, but the plectra are regulated to engage at about the same time and with the same amount of force. It would probably be fairly easy to design or adjust a harpsichord so that one set of jacks had its plectra set to engage sooner than the rest, and operate with less force, so as to allow a performer to either play individual notes using just that set of jacks, using all activated sets, or initially on that set of jacks and then on the other sets after a short delay. I don't know how often instruments would be deliberately designed to work that way, either in Bach's time or in more modern times, but designing them to do so would be fairly easy.